The use of humanized tumor-targeting molecules in cancer therapeutics has seen remarkable success in recent years. In particular, antibody-based therapies have proven to be an important strategy for treating patients with hematological malignancies and tumors. However, current treatments can also provoke immune reactions against a wide range of normal cells (e.g., a patient's B lymphocytes), resulting in serious side effects. Thus, an immediate clinical need exists for cancer therapeutics with increased targeting selectivity (e.g., the ability to selectively target cancer cells). The present disclosure provides safer and less toxic compositions and methods for cancer therapy that overcome the limitations of conventional therapies.